The initiatives, expected to be announced by the end of the week, would limit China's ability to invest in the U.S. tech sector, and block additional technology exports to Beijing.

Tech sectors likely to be targeted are those China hopes to develop under its Made in China 2025 report to become a global leader in 10 broad areas of tech: information technology, robotics, aerospace and aviation equipment, energy-efficient vehicles and electrical equipment, among others.

Trump's plan, first reported by the Wall Street Journal late Sunday, immediately drew a cautionary note from the trade group Information Technology Industry Council, whose members include Apple (AAPL), Amazon.com (AMZN) and Alphabet (GOOGL).

ITIC spokesman Jose Castaneda tells Barron's the administration should "carefully consider the consequences and end goal" of its plan. He says a bill in the Senate that would revamp the Committee on Foreign Investment in the United States and more strictly limit the transfer of sensitive technology to adversary countries "strikes the right balance of protecting national security concerns while not impeding innovation and economic growth."

Linda Moore, Chief Executive of TechNet, a trade group whose members include Facebook (FB), Microsoft (MSFT), and AT&T (T), says steep tariffs on tech goods from China hurt the industry's bottom line and are a "mistake."

China's influence on tech runs far and deep. A recent study by the U.S.-China Economic and Security Review Commission concluded seven major American tech companies--Cisco Systems (CSCO), Dell Technologies (DVMT), HP (HPQ), IBM (IBM), Intel (INTC), Microsoft, and Unisys (UIS)--source more than half of their products and components from China.

Shares of Intel, Microsoft, HP, IBM, Cisco, Dell, and Unisys all declined today in a big sell-off for tech.

Indeed, recent comments suggest companies in the global tech supply chain are bracing for disruptions. Last week, Terry Gou, chairman of Foxconn Technology Group--a key iPhone assembler that will bring an assembly facility to Wisconsin and create up to 13,000 new jobs--told shareholders at the company's annual meeting in Taiwan that "we have a number of response plans."

"The trade war is not about trade, but it is a tech war, and it is a manufacturing war," Gou said.

Among the most vulnerable companies is Apple, which has bet big in China. Nearly 20% of its fiscal year revenue ($44.8 billion) came from the region, where it shipped more than 41 million iPhones in that same time. Apple shares are down more than 2% today, to $180.86. [Apple did not immediately respond to an email seeking comment on Trump's plan.]

While Apple CEO Tim Cook has received assurances from Trump that iPhones built in China would not be affected by tariffs, Apple could be at serious risk if China clamps down on its suppliers. Cook is one of the few tech executives to speak up on the matter.

"I talked about trade and the importance of trade, and how I felt that two countries trading together make the pie larger," Cook said last month in an interview with Carlyle Group co-founder David Rubenstein of his April meeting at the White House. "I felt that tariffs were not the right approach there. I showed [Trump] some analytical kind of things to demonstrate why."

Apple's exposure is the most severe among the so-called Faang companies because of its commitment to China.

Facebook (FB) is blocked in China, and Netflix (NFLX) and Amazon have minimal presences. Alphabet's Google search function is blocked in the country although it has a presence in China through the Android operating system.

"We continue to strongly believe that, given the primarily services nature of traditional Faang names and very internationally distributed from a revenue perspective with China representing negligible revenue/growth, that Facebook, Amazon, Netflix, and Google/Alphabet are 'primarily insulated' from tariff worries and a potential retaliatory trade war with China if negotiations fail to result in a path to an agreement over the coming weeks," Daniel Ives, head of technology research at GBH Insights, wrote in a note to clients last week.

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